Handle edge cases in basic JSON.stringify.

BUG=

Review URL: https://chromiumcodereview.appspot.com/11315009

git-svn-id: http://v8.googlecode.com/svn/branches/bleeding_edge@12842 ce2b1a6d-e550-0410-aec6-3dcde31c8c00
This commit is contained in:
yangguo@chromium.org 2012-11-02 14:46:57 +00:00
parent 64793b3f0d
commit e8d91b424c
4 changed files with 227 additions and 217 deletions

View File

@ -46,7 +46,7 @@ class BasicJsonStringifier BASE_EMBEDDED {
static const int kMaxPartLength = 16 * 1024;
static const int kPartLengthGrowthFactor = 2;
enum Result { UNCHANGED, SUCCESS, BAILOUT, CIRCULAR, STACK_OVERFLOW };
enum Result { UNCHANGED, SUCCESS, EXCEPTION, CIRCULAR, STACK_OVERFLOW };
template <bool is_ascii> void Extend();
@ -79,27 +79,36 @@ class BasicJsonStringifier BASE_EMBEDDED {
Handle<Object> GetProperty(Handle<JSObject> object,
Handle<String> key);
bool MayHaveToJsonFunction(Handle<JSObject> object);
Handle<Object> ApplyToJsonFunction(Handle<Object> object,
Handle<Object> key);
INLINE(Result Serialize(Handle<Object> object)) {
return Serialize_<false>(object);
// Entry point to serialize the object.
INLINE(Result SerializeObject(Handle<Object> obj)) {
return Serialize_<false>(obj, false, isolate_->factory()->empty_string());
}
INLINE(Result SerializeDeferred(Handle<Object> object,
bool deferred_comma,
Handle<String> deferred_key)) {
// Serialize an array element.
// The index may serve as argument for the toJSON function.
INLINE(Result SerializeElement(Handle<Object> object, int i)) {
return Serialize_<false>(object, false, Handle<Object>(Smi::FromInt(i)));
}
// Serialize a object property.
// The key may or may not be serialized depending on the property.
// The key may also serve as argument for the toJSON function.
INLINE(Result SerializeProperty(Handle<Object> object,
bool deferred_comma,
Handle<String> deferred_key)) {
ASSERT(!deferred_key.is_null());
return Serialize_<true>(object, deferred_comma, deferred_key);
}
template <bool deferred_key>
Result Serialize_(Handle<Object> object,
bool comma = false,
Handle<String> key = Handle<String>::null());
template <bool deferred_string_key>
Result Serialize_(Handle<Object> object, bool comma, Handle<Object> key);
void SerializeDeferredKey(bool deferred_comma, Handle<String> deferred_key) {
void SerializeDeferredKey(bool deferred_comma, Handle<Object> deferred_key) {
if (deferred_comma) Append(',');
SerializeString(deferred_key);
SerializeString(Handle<String>::cast(deferred_key));
Append(':');
}
@ -110,8 +119,12 @@ class BasicJsonStringifier BASE_EMBEDDED {
return SerializeDouble(object->value());
}
INLINE(Result SerializeArray(Handle<JSArray> object));
INLINE(Result SerializeObject(Handle<JSObject> object));
Result SerializeJSValue(Handle<JSValue> object);
INLINE(Result SerializeJSArray(Handle<JSArray> object));
INLINE(Result SerializeJSObject(Handle<JSObject> object));
Result SerializeJSArraySlow(Handle<JSArray> object, int length);
void SerializeString(Handle<String> object);
@ -207,19 +220,19 @@ BasicJsonStringifier::BasicJsonStringifier(Isolate* isolate)
MaybeObject* BasicJsonStringifier::Stringify(Handle<Object> object) {
switch (Serialize(object)) {
switch (SerializeObject(object)) {
case UNCHANGED:
return isolate_->heap()->undefined_value();
case SUCCESS:
ShrinkCurrentPart();
return *isolate_->factory()->NewConsString(accumulator(), current_part_);
case UNCHANGED:
return isolate_->heap()->undefined_value();
case CIRCULAR:
return isolate_->Throw(*isolate_->factory()->NewTypeError(
"circular_structure", HandleVector<Object>(NULL, 0)));
case STACK_OVERFLOW:
return isolate_->StackOverflow();
default:
return Smi::FromInt(0);
return Failure::Exception();
}
}
@ -261,36 +274,34 @@ Handle<Object> BasicJsonStringifier::GetProperty(Handle<JSObject> object,
}
case CONSTANT_FUNCTION:
return Handle<Object>(lookup.GetConstantFunction());
case CALLBACKS:
case HANDLER:
case INTERCEPTOR:
return Handle<Object>::null();
case TRANSITION:
case NONEXISTENT:
UNREACHABLE();
break;
default: {
PropertyAttributes attr;
return Object::GetProperty(object, object, &lookup, key, &attr);
}
}
return Handle<Object>::null();
}
bool BasicJsonStringifier::MayHaveToJsonFunction(Handle<JSObject> object) {
Handle<Object> BasicJsonStringifier::ApplyToJsonFunction(
Handle<Object> object, Handle<Object> key) {
LookupResult lookup(isolate_);
object->LookupRealNamedProperty(*tojson_symbol_, &lookup);
if (!lookup.IsProperty()) return false;
Object* value;
switch (lookup.type()) {
case NORMAL:
value = lookup.holder()->GetNormalizedProperty(&lookup);
break;
case FIELD:
value = lookup.holder()->FastPropertyAt(lookup.GetFieldIndex());
break;
default:
return true;
}
ASSERT(!value->IsTheHole());
return value->IsSpecFunction();
JSObject::cast(*object)->LookupRealNamedProperty(*tojson_symbol_, &lookup);
if (!lookup.IsProperty()) return object;
PropertyAttributes attr;
Handle<Object> fun =
Object::GetProperty(object, object, &lookup, tojson_symbol_, &attr);
if (!fun->IsJSFunction()) return object;
// Call toJSON function.
if (key->IsSmi()) key = isolate_->factory()->NumberToString(key);
Handle<Object> argv[] = { key };
bool has_exception = false;
HandleScope scope(isolate_);
object = Execution::Call(fun, object, 1, argv, &has_exception);
// Return empty handle to signal an exception.
if (has_exception) return Handle<Object>::null();
return scope.CloseAndEscape(object);
}
@ -319,51 +330,49 @@ void BasicJsonStringifier::StackPop() {
}
template <bool deferred_key>
template <bool deferred_string_key>
BasicJsonStringifier::Result BasicJsonStringifier::Serialize_(
Handle<Object> object, bool comma, Handle<String> key) {
Handle<Object> object, bool comma, Handle<Object> key) {
if (object->IsJSObject()) {
// We don't deal with custom toJSON functions.
if (MayHaveToJsonFunction(Handle<JSObject>::cast(object))) return BAILOUT;
object = ApplyToJsonFunction(object, key);
if (object.is_null()) return EXCEPTION;
}
if (object->IsJSFunction()) {
return UNCHANGED;
} else if (object->IsJSArray()) {
if (deferred_key) SerializeDeferredKey(comma, key);
return SerializeArray(Handle<JSArray>::cast(object));
if (object->IsJSObject()) {
if (object->IsJSFunction()) return UNCHANGED;
if (deferred_string_key) SerializeDeferredKey(comma, key);
if (object->IsJSArray()) {
return SerializeJSArray(Handle<JSArray>::cast(object));
} else if (object->IsJSValue()) {
// JSValue with a custom prototype.
if (object->GetPrototype()->IsJSReceiver()) return BAILOUT;
// Unpack value wrapper and fall through.
object = Handle<Object>(JSValue::cast(*object)->value());
return SerializeJSValue(Handle<JSValue>::cast(object));
} else {
if (deferred_key) SerializeDeferredKey(comma, key);
return SerializeObject(Handle<JSObject>::cast(object));
return SerializeJSObject(Handle<JSObject>::cast(object));
}
}
// Handle non-JSObject.
if (object->IsString()) {
if (deferred_key) SerializeDeferredKey(comma, key);
if (deferred_string_key) SerializeDeferredKey(comma, key);
SerializeString(Handle<String>::cast(object));
return SUCCESS;
} else if (object->IsSmi()) {
if (deferred_key) SerializeDeferredKey(comma, key);
if (deferred_string_key) SerializeDeferredKey(comma, key);
return SerializeSmi(Smi::cast(*object));
} else if (object->IsHeapNumber()) {
if (deferred_key) SerializeDeferredKey(comma, key);
if (deferred_string_key) SerializeDeferredKey(comma, key);
return SerializeHeapNumber(Handle<HeapNumber>::cast(object));
} else if (object->IsOddball()) {
switch (Oddball::cast(*object)->kind()) {
case Oddball::kFalse:
if (deferred_key) SerializeDeferredKey(comma, key);
if (deferred_string_key) SerializeDeferredKey(comma, key);
Append("false");
return SUCCESS;
case Oddball::kTrue:
if (deferred_key) SerializeDeferredKey(comma, key);
if (deferred_string_key) SerializeDeferredKey(comma, key);
Append("true");
return SUCCESS;
case Oddball::kNull:
if (deferred_key) SerializeDeferredKey(comma, key);
if (deferred_string_key) SerializeDeferredKey(comma, key);
Append("null");
return SUCCESS;
}
@ -373,6 +382,29 @@ BasicJsonStringifier::Result BasicJsonStringifier::Serialize_(
}
BasicJsonStringifier::Result BasicJsonStringifier::SerializeJSValue(
Handle<JSValue> object) {
bool has_exception = false;
String* class_name = object->class_name();
if (class_name == isolate_->heap()->String_symbol()) {
Handle<Object> value = Execution::ToString(object, &has_exception);
if (has_exception) return EXCEPTION;
SerializeString(Handle<String>::cast(value));
} else if (class_name == isolate_->heap()->Number_symbol()) {
Handle<Object> value = Execution::ToNumber(object, &has_exception);
if (has_exception) return EXCEPTION;
if (value->IsSmi()) return SerializeSmi(Smi::cast(*value));
SerializeHeapNumber(Handle<HeapNumber>::cast(value));
} else {
ASSERT(class_name == isolate_->heap()->Boolean_symbol());
Object* value = JSValue::cast(*object)->value();
ASSERT(value->IsBoolean());
Append(value->IsTrue() ? "true" : "false");
}
return SUCCESS;
}
BasicJsonStringifier::Result BasicJsonStringifier::SerializeSmi(Smi* object) {
static const int kBufferSize = 100;
char chars[kBufferSize];
@ -396,7 +428,7 @@ BasicJsonStringifier::Result BasicJsonStringifier::SerializeDouble(
}
BasicJsonStringifier::Result BasicJsonStringifier::SerializeArray(
BasicJsonStringifier::Result BasicJsonStringifier::SerializeJSArray(
Handle<JSArray> object) {
HandleScope handle_scope(isolate_);
Result stack_push = StackPush(object);
@ -405,8 +437,7 @@ BasicJsonStringifier::Result BasicJsonStringifier::SerializeArray(
Append('[');
switch (object->GetElementsKind()) {
case FAST_SMI_ELEMENTS: {
Handle<FixedArray> elements = Handle<FixedArray>(
FixedArray::cast(object->elements()));
Handle<FixedArray> elements(FixedArray::cast(object->elements()));
for (int i = 0; i < length; i++) {
if (i > 0) Append(',');
SerializeSmi(Smi::cast(elements->get(i)));
@ -414,7 +445,7 @@ BasicJsonStringifier::Result BasicJsonStringifier::SerializeArray(
break;
}
case FAST_DOUBLE_ELEMENTS: {
Handle<FixedDoubleArray> elements = Handle<FixedDoubleArray>(
Handle<FixedDoubleArray> elements(
FixedDoubleArray::cast(object->elements()));
for (int i = 0; i < length; i++) {
if (i > 0) Append(',');
@ -423,11 +454,10 @@ BasicJsonStringifier::Result BasicJsonStringifier::SerializeArray(
break;
}
case FAST_ELEMENTS: {
Handle<FixedArray> elements = Handle<FixedArray>(
FixedArray::cast(object->elements()));
Handle<FixedArray> elements(FixedArray::cast(object->elements()));
for (int i = 0; i < length; i++) {
if (i > 0) Append(',');
Result result = Serialize(Handle<Object>(elements->get(i)));
Result result = SerializeElement(Handle<Object>(elements->get(i)), i);
if (result == SUCCESS) continue;
if (result == UNCHANGED) {
Append("null");
@ -437,8 +467,14 @@ BasicJsonStringifier::Result BasicJsonStringifier::SerializeArray(
}
break;
}
default:
return BAILOUT;
// TODO(yangguo): The FAST_HOLEY_* cases could be handled in a faster way.
// They resemble the non-holey cases except that a prototype chain lookup
// is necessary for holes.
default: {
Result result = SerializeJSArraySlow(object, length);
if (result != SUCCESS) return result;
break;
}
}
Append(']');
StackPop();
@ -447,16 +483,40 @@ BasicJsonStringifier::Result BasicJsonStringifier::SerializeArray(
}
BasicJsonStringifier::Result BasicJsonStringifier::SerializeObject(
BasicJsonStringifier::Result BasicJsonStringifier::SerializeJSArraySlow(
Handle<JSArray> object, int length) {
for (int i = 0; i < length; i++) {
if (i > 0) Append(',');
Handle<Object> element = Object::GetElement(object, i);
if (element->IsUndefined()) {
Append("null");
} else {
Result result = SerializeElement(element, i);
if (result == SUCCESS) continue;
if (result == UNCHANGED) {
Append("null");
} else {
return result;
}
}
}
return SUCCESS;
}
BasicJsonStringifier::Result BasicJsonStringifier::SerializeJSObject(
Handle<JSObject> object) {
HandleScope handle_scope(isolate_);
Result stack_push = StackPush(object);
if (stack_push != SUCCESS) return stack_push;
if (object->IsJSGlobalProxy()) return BAILOUT;
bool threw = false;
if (object->IsJSGlobalProxy()) {
object = Handle<JSObject>(JSObject::cast(object->GetPrototype()));
ASSERT(object->IsGlobalObject());
}
bool has_exception = false;
Handle<FixedArray> contents =
GetKeysInFixedArrayFor(object, LOCAL_ONLY, &threw);
if (threw) return BAILOUT;
GetKeysInFixedArrayFor(object, LOCAL_ONLY, &has_exception);
if (has_exception) return EXCEPTION;
Append('{');
bool comma = false;
for (int i = 0; i < contents->length(); i++) {
@ -478,10 +538,10 @@ BasicJsonStringifier::Result BasicJsonStringifier::SerializeObject(
property = GetProperty(object, key_handle);
}
}
if (property.is_null()) return BAILOUT;
Result result = SerializeDeferred(property, comma, key_handle);
if (property.is_null()) return EXCEPTION;
Result result = SerializeProperty(property, comma, key_handle);
if (!comma && result == SUCCESS) comma = true;
if (result >= BAILOUT) return result;
if (result >= EXCEPTION) return result;
}
Append('}');
StackPop();

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@ -178,143 +178,9 @@ function JSONSerialize(key, holder, replacer, stack, indent, gap) {
}
function BasicSerializeArray(value, stack, builder) {
var len = value.length;
if (len == 0) {
builder.push("[]");
return;
}
if (!%PushIfAbsent(stack, value)) {
throw MakeTypeError('circular_structure', $Array());
}
builder.push("[");
var val = value[0];
if (IS_STRING(val)) {
// First entry is a string. Remaining entries are likely to be strings too.
var array_string = %QuoteJSONStringArray(value);
if (!IS_UNDEFINED(array_string)) {
// array_string also includes bracket characters so we are done.
builder[builder.length - 1] = array_string;
stack.pop();
return;
} else {
builder.push(%QuoteJSONString(val));
for (var i = 1; i < len; i++) {
val = value[i];
if (IS_STRING(val)) {
builder.push(%QuoteJSONStringComma(val));
} else {
builder.push(",");
var before = builder.length;
BasicJSONSerialize(i, val, stack, builder);
if (before == builder.length) builder[before - 1] = ",null";
}
}
}
} else if (IS_NUMBER(val)) {
// First entry is a number. Remaining entries are likely to be numbers too.
builder.push(JSON_NUMBER_TO_STRING(val));
for (var i = 1; i < len; i++) {
builder.push(",");
val = value[i];
if (IS_NUMBER(val)) {
builder.push(JSON_NUMBER_TO_STRING(val));
} else {
var before = builder.length;
BasicJSONSerialize(i, val, stack, builder);
if (before == builder.length) builder[before - 1] = ",null";
}
}
} else {
var before = builder.length;
BasicJSONSerialize(0, val, stack, builder);
if (before == builder.length) builder.push("null");
for (var i = 1; i < len; i++) {
builder.push(",");
before = builder.length;
BasicJSONSerialize(i, value[i], stack, builder);
if (before == builder.length) builder[before - 1] = ",null";
}
}
stack.pop();
builder.push("]");
}
function BasicSerializeObject(value, stack, builder) {
if (!%PushIfAbsent(stack, value)) {
throw MakeTypeError('circular_structure', $Array());
}
builder.push("{");
var first = true;
var keys = %ObjectKeys(value);
var len = keys.length;
for (var i = 0; i < len; i++) {
var p = keys[i];
if (!first) {
builder.push(%QuoteJSONStringComma(p));
} else {
builder.push(%QuoteJSONString(p));
}
builder.push(":");
var before = builder.length;
BasicJSONSerialize(p, value[p], stack, builder);
if (before == builder.length) {
builder.pop();
builder.pop();
} else {
first = false;
}
}
stack.pop();
builder.push("}");
}
function BasicJSONSerialize(key, value, stack, builder) {
if (IS_SPEC_OBJECT(value)) {
var toJSON = value.toJSON;
if (IS_SPEC_FUNCTION(toJSON)) {
value = %_CallFunction(value, ToString(key), toJSON);
}
}
if (IS_STRING(value)) {
builder.push(value !== "" ? %QuoteJSONString(value) : '""');
} else if (IS_NUMBER(value)) {
builder.push(JSON_NUMBER_TO_STRING(value));
} else if (IS_BOOLEAN(value)) {
builder.push(value ? "true" : "false");
} else if (IS_NULL(value)) {
builder.push("null");
} else if (IS_SPEC_OBJECT(value) && !(typeof value == "function")) {
// Value is a non-callable object.
// Unwrap value if necessary
if (IS_NUMBER_WRAPPER(value)) {
value = ToNumber(value);
builder.push(JSON_NUMBER_TO_STRING(value));
} else if (IS_STRING_WRAPPER(value)) {
builder.push(%QuoteJSONString(ToString(value)));
} else if (IS_BOOLEAN_WRAPPER(value)) {
builder.push(%_ValueOf(value) ? "true" : "false");
} else if (IS_ARRAY(value)) {
BasicSerializeArray(value, stack, builder);
} else {
BasicSerializeObject(value, stack, builder);
}
}
}
function JSONStringify(value, replacer, space) {
if (%_ArgumentsLength() == 1) {
var result = %BasicJSONStringify(value);
if (result != 0) return result;
var builder = new InternalArray();
BasicJSONSerialize('', value, new InternalArray(), builder);
if (builder.length == 0) return;
result = %_FastAsciiArrayJoin(builder, "");
if (!IS_UNDEFINED(result)) return result;
return %StringBuilderConcat(builder, builder.length, "");
return %BasicJSONStringify(value);
}
if (IS_OBJECT(space)) {
// Unwrap 'space' if it is wrapped
@ -340,6 +206,7 @@ function JSONStringify(value, replacer, space) {
return JSONSerialize('', {'': value}, replacer, new InternalArray(), "", gap);
}
function SetUpJSON() {
%CheckIsBootstrapping();
InstallFunctions($JSON, DONT_ENUM, $Array(

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@ -27,6 +27,89 @@
// Flags: --allow-natives-syntax
// Test JSON.stringify on the global object.
var a = 12345;
assertTrue(JSON.stringify(this).indexOf('"a":12345') > 0);
// Test JSON.stringify of array in dictionary mode.
var array_1 = [];
var array_2 = [];
array_1[100000] = 1;
array_2[100000] = function() { return 1; };
var nulls = "";
for (var i = 0; i < 100000; i++) {
nulls += 'null,';
}
expected_1 = '[' + nulls + '1]';
expected_2 = '[' + nulls + 'null]';
assertEquals(expected_1, JSON.stringify(array_1));
assertEquals(expected_2, JSON.stringify(array_2));
// Test JSValue with custom prototype.
var num_wrapper = Object(42);
num_wrapper.__proto__ = { __proto__: null,
toString: function() { return true; } };
assertEquals('1', JSON.stringify(num_wrapper));
var str_wrapper = Object('2');
str_wrapper.__proto__ = { __proto__: null,
toString: function() { return true; } };
assertEquals('"true"', JSON.stringify(str_wrapper));
var bool_wrapper = Object(false);
bool_wrapper.__proto__ = { __proto__: null,
toString: function() { return true; } };
// Note that toString function is not evaluated here!
assertEquals('false', JSON.stringify(bool_wrapper));
// Test getters.
var counter = 0;
var getter_obj = { get getter() {
counter++;
return 123;
} };
assertEquals('{"getter":123}', JSON.stringify(getter_obj));
assertEquals(1, counter);
// Test toJSON function.
var tojson_obj = { toJSON: function() {
counter++;
return [1, 2];
},
a: 1};
assertEquals('[1,2]', JSON.stringify(tojson_obj));
assertEquals(2, counter);
// Test that we don't recursively look for the toJSON function.
var tojson_proto_obj = { a: 'fail' };
tojson_proto_obj.__proto__ = { toJSON: function() {
counter++;
return tojson_obj;
} };
assertEquals('{"a":1}', JSON.stringify(tojson_proto_obj));
// Test toJSON produced by a getter.
var tojson_via_getter = { get toJSON() {
return function(x) {
counter++;
return 321;
};
},
a: 1 };
assertEquals('321', JSON.stringify(tojson_via_getter));
// Test toJSON with key.
tojson_obj = { toJSON: function(key) { return key + key; } };
var tojson_with_key_1 = { a: tojson_obj, b: tojson_obj };
assertEquals('{"a":"aa","b":"bb"}', JSON.stringify(tojson_with_key_1));
var tojson_with_key_2 = [ tojson_obj, tojson_obj ];
assertEquals('["00","11"]', JSON.stringify(tojson_with_key_2));
// Test toJSON with exception.
var tojson_ex = { toJSON: function(key) { throw "123" } };
assertThrows(function() { JSON.stringify(tojson_ex); });
// Test holes in arrays.
var fast_smi = [1, 2, 3, 4];
fast_smi.__proto__ = [7, 7, 7, 7];
delete fast_smi[2];

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@ -37,5 +37,5 @@ for (var i = 0; i < 10000; i++) a.push(new_space_string);
// screw up reading from the correct location.
json1 = JSON.stringify(a);
json2 = JSON.stringify(a);
assertEquals(json1, json2);
assertEquals(json1, json2, "GC caused JSON.stringify to fail.");